This section is intended to provide a background or context to the invention recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Power generation systems and facilities that use steam as a working fluid (e.g. Rankine cycle systems, etc.) in which a source of thermal energy converts a feedwater to steam to drive a turbine and generator in simple or combined cycle operation are generally known. In such power generation systems, the steam exiting the turbine is typically condensed and then returned to the system as feedwater to complete the thermodynamic cycle. In some systems, a cooling tower, such as a wet cooling tower, is used to condense the steam for reuse in the power generation cycle. During the cooling and evaporation process, dissolved minerals tend to accumulate in the condensate within the cooling tower until the total dissolved solids (TDS) reaches an upper limit established for proper operation of the power generation system. In order to maintain TDS levels within acceptable limits, draw-off or blowdown of the condensate is frequently conducted and fresh make-up water must be added to the system to compensate for the removal of the water from blowdown. Typically, cooling tower blowdown in simple or combined cycle power generation plants amounts to one of the plant's largest sources of water discharge and the need for separate processing of the blowdown water to prevent environmental contamination.
Accordingly, it would be desirable to provide a system and method that can substantially reduce (or eliminate) cooling tower blowdown wastewater discharge. It would also be desirable to provide a system and method that produced pressurized steam for process heating or electric generation. It would also be desirable to provide a system and method that could process and return most of the cooling tower blowdown wastewater as distilled water that can be reused in the power generation plant and that can separate the collected contaminants (e.g. salts, etc.) for use in other applications.